Research Areas

Heavy Element Chemistry

This activity supports basic research in the chemistry of the heavy elements, focused on the actinides, but also includes the transactinide elements and some fission products. The unique molecular bonding of these elements is explored using experiment and theory to elucidate electronic and molecular structure as well as reaction thermodynamics. Emphasis is placed on resolving the f-electron challenge; the chemical and physical properties of these elements to determine solution, interfacial and solid-state bonding and reactivity; fundamental transactinide chemical properties; fundamental science underpinning the extraction and separation of the actinides; and on bonding relationships among the actinides, lanthanides, and transition metals.

Resolving the chemistry and physics of f-electrons is one of the grand challenges of science for energy technology. Research to meet this challenge is pursued in the HEC program and includes efforts aimed at implementing quantum-mechanical theories that more adequately describe spin-orbit interactions and relativistic effects, and efforts to expand our ability to predict actinide and fission product chemical behavior under conditions relevant to all stages of fuel reprocessing.

Synthetic and spectroscopic research is pursued within the HEC program on chemical bonding and reactivity of molecules that contain heavy elements and of actinides in environmentally relevant species, with a focus on gaining a fundamental understanding of separations processes and aiding the development of ligands to sequester actinides. Better characterization and modeling of the interactions of actinides at liquid-solid and liquid-liquid interfaces, including mineral surfaces under environmentally relevant conditions and as colloids, is motivated by improving the separations processes that are essential for advanced nuclear fuel cycles and improving models of actinide environmental transport.